Field of the Invention
This disclosure relates to an integrated semiconductor device and a manufacturing method therefor, and in particular to an integrated semiconductor device comprising a resistor and a manufacturing method therefor.
Description of the Related Art
An integrated semiconductor device usually comprises a field effect transistor.
As for a gate stacked structure of a conventional field effect transistor, a gate layer thereof generally comprises a conductive material such as polysilicon, and a gate dielectric layer thereof generally comprises a dielectric material such as silicon oxide.
As the size of a semiconductor device decreases continuously, it is a widely-adopted practice in the industry to employ a conductive material comprising a metal element (also called a metal material) to form the gate layer and employ a dielectric material with a high dielectric constant (also called a high-K dielectric material) to form the gate dielectric layer. This is the so-called high-K dielectric-metal gate (HKMG) process.
In addition to field effect transistors, the integrated semiconductor device may comprise one or more resistors.
A conventional resistor is generally formed of doped polysilicon, and usually uses a block layer to avoid reducing the resistance of the resistor due to silicidation.
U.S. Pat. No. 7,749,822 B2 discloses a method for forming a gate stacked structure of a field effect transistor in a field effect transistor region and a resistor in a resistor region. The gate stacked structure and the resistor are formed from a stacked structure of a dielectric layer, a conductive layer and a polysilicon layer. In this method, in the resistor region, the conductive layer on the dielectric layer and an un-doped polysilicon layer on a middle portion of the conductive layer serve together as a resistor body, a doped polysilicon layer on distal ends of the conductive layer serves as resistor terminals, and there are contacts electrically connected to the resistor terminals. Alternatively, the conductive layer on the dielectric layer itself serves as a resistor body, and there are contacts electrically connected to distal ends of the conductive layer. The conductive layer is, for example, a metal layer comprising titanium nitride (TiN) or tantalum carbide (TaC), and is, for example, a thin layer having a thickness of about 1 nm to about 7 nm.
However, the inventor of the present invention has realized that, in a semiconductor manufacturing process such as that in U.S. Pat. No. 7,749,822 B2, the resistance value of the resistor is usually small. This is especially true in a case where the resistor is formed of a material with high conductivity (such as a metal material). In some applications, it is desired to obtain high resistance value of a resistor.